Solar power is the harnessing of the sun's energy through either active or passive means. Active Solar consists mainly of the usage of photovoltaic cells; when sunlight hits the cells, it knocks the electrons free from the atoms, and the freed electrons then move through the cell, generating electricity along the way. Another active method to capture the sun's energy is the solar thermal power plant. In the power plant, there are two methods to capture the sun's heat: the first uses u-shaped mirrors to focus the rays on a oil pipe, which then heats water to drive a steam turbine. The second works similarly, except with moveable mirrors that focus the sun on a collector tower, in which there is a reciever. Molten salt runs through the reciever and runs a generator. Passive solar uses solar power indirectly to heat, for example, a house. Among the strategies used is one that encloses water pipes in a black box on the roof. The black metal absorbs heat and warms the water, which the residents then use for showers, laundry, etc. Another method uses windows on the sunniest side of the building to warm heat-absorbant materials inside the house. This is called direct gain. These materials are designed to release energy during the night to heat the house. Source: National Geographic
Pros
Renewable
Abundance
Capturing it is green
Not noisy
Both electric and thermal power
Generating electricity from photovoltaic cells gives the highest power denisty of all of the renewable sources
No increasing prices
Ideal for remote locations or anywhere
Reduces the use of fossil fuel
Readily avalible throughout the world, so countries won't be dependent on other countries for energy like oil.
You do not necessarily need to connect to a power grid to use it (Source)
external image solar-panel-diagram.gif
Cons
Manufactoring emits pollutants, greenhouse gases worse than CO2.
Has to be a long-term investment - expensive at first.
Solar power can not be used at night, and a system could cost between 15,000 and 30,000 dollars. To save that kind of money, it could take from three to ten years, depending on the cost of the panels and the amount of energy you need.
Weather & pollution can affect the power output.
Shady and tree covered areas also do not have great power output.
Not much competition, so prices are driven up.
You need a relatively large area to install solar panels if you want a good level of efficiency. (Source)
Depending where you live (Arizona vs. Alaska, around many shady trees or in the desert, etc.), you will get different results with solar energy systems.(Source)
The Renewable Portfolio Standard Requires the states to obtain a certain amount of clean energy. For example, Arizona must get 15% of their energy from renewable sources by 2025. Jeff Bingaman (D-New Mexico) speaking for the Senate Energy and Natural Resources Committee, has also proposed a bill for extending the tax credit and the Clean Energy Standard Act of 2012, requiring large utilities to obtain a certain percentage of their energy from clean sources. The percent grows with time.
Potential
Solar Energy has enormous potential not only for the United States, but around the world. Even though enough sunlight falls on Earth's surface every hour to meet the world's energy demand for a year, only approximately 10,000 homes in the United States are powered entirely by solar energy - approximately 9% of the whole. It would only take around 0.3% of the world's surface to meet our electric needs via solar power - that is about the amount of roof space in Australia. The silicon (used in photovoltaic cells) from just one ton of sand can produce as much electricity as burning 500,000 tons of coal. Solar energy is also an extremely diverse source; you can use it electrically, thermally, or for basic functions such as cooking. The largest Concentrated solar power (CSP) solar power plant is in the world located in the Mojave Desert of California, and the largest photovoltaic (PV) solar power plant in the world is located in Golmud Solar Park in China (Alliant Kids Energy). Solar Power also is a much more viable option than, for example, nuclear power. Weight for weight, advanced silicon based solar cells generate the same amount of electricity over their lifetime as nuclear fuel rods, without the hazardous waste. All the components in a solar panel can be recycled, whereas nuclear waste remains a threat for thousands of years. Also, both solar and wind power systems have 100 times better lifetime energy yield than either nuclear or fossil energy system per ton of mined materials (Energy Matters). A future for soolar power also exists in transportation; NASA powers many of its spacecraft with solar energy. In addition, an aircraft power solely by the sun crossed the USA in 1990 (Source). Source: Green Living
Current Events
The U.S. Government spent 1.4 billion dollars making a solar power plant to power around 140,000 homes. Source
Lincoln Renewable Energy officially dedicated it's 12.5 mega-watt NJ Oak solar project, which consists of 53,000 solar panels over a 100-acre farm.
Over 150 residents of North Carolina are now generating power from solar panels mounted on their rooftops. This initiative was sponsored by Progress Energy, who is offering consumers rebates for using solar energy.
$200,000 was awarded to University students who initiated start-ups focused around solar panel-cleaning robots for 20% more efficiency, along with waste-water conversion into usable energy. Source
Statistics
Average solar panel size needed to power the average home
600 sq ft.
Average cost of installing a 600 sq ft solar system
$55,000
Solar energy share of global energy consumption
.07%
Average annual growth rate of global solar energy capacity
102%
Amount of solar energy that hits the earth each year
8.2 Million Quads
Total quads currently used by the entire globe annually
400 Quads
Percent of earth that would need to be covered with solar panels to power it
0.0005 %
Barrels of oil saved annually by all solar energy users
75 Million Barrels
Tons of carbon dioxide saved annually by all solar energy users
The general population will benefit from switching to solar energy. Although it is a long term investment, switching to solar energy will pay off after several years. However, those working in coal and mining industries will suffer, because of lack of jobs, if the globe goes solar. That said, they could find new jobs working in solar businesses, doing repair work, or creating solar panels.
Wind Power
Wind power is the usage of wind to generate energy through wind turbines. Wind is a free, renewable resource, with great abundance everywhere on the planet. This energy is ideal for remote locations, though it can be used anywhere. Since it can be used anywhere, if the whole world converted to using wind energy, countries would not be in debt because of reliance on other countries for oil and fossil fuels. However, the wind turbines must be a long investment, due to the great expense of each turbine - although, with the amount of money saved through the wind turbine, the wind turbine will soon pay for itself. They also generate a lot of noise, contributing to noise pollution, and can kill birds and bats. An average wind speed of 14 miles per hour is needed to convert wind energy into electricity. Wind farms currently produce enough electricity to meet the needs of more than 600,000 families in the United States.
One wind turbine can provide enough electricity to power up to 300 homes. Wind power farms generate between 17 and 39 times as much power as they consume, as compared to 16 times for nuclear plants and 11 times for coal plants, according to a study of Midwestern wind farms by the University of Wisconsin. The average blade length is 80 feet. The height of the tower must be four times the length of the blade. Wind is caused by uneven atmospheric heating, the rotation of the earth, and the Earth's surface irregularities. Patterns of wind flow are altered by vegetation, bodies of water, and the earth's terrain. Wind turbines modify the kinetic energy found in wind, and turn it into mechanical power. The wind turns the blades, which spin a shaft, which are hooked up to a generator that makes electricity. This energy is sent to a utility grid which sends it to consumers of energy through transmission and distribution lines. Source
Readily available throughout the world, so countries won't be dependent on other countries for energy like oil.
Reduces electricity bills
Can create jobs to make and maintain the wind turbines
Cons
Has to be a long-term investment - it is expensive at first, and could take between three and eight years to pay off a single turbine
Weather can affect the power output
Expensive to install
Birds and bats can be killed by wind turbines - however, the 20,000 killed annually is insignificant compared to the 175,000,000 killed yearly by transmission lines.
Turbines may create a lot of noise, contributing to noise pollution.
Potential aesthetic compromise
There are many remote wind sites, because wind turbines take up a lot of space, so transportation of the supply might be limited
Wind turbines take up space, and alternate uses for the land might be considered more important
http://www.darvill.clara.net/altenerg/wind.htm
Federal Policy
The United States Congress has passed and extended several pieces of legislation to promote the use of renewable energy. "Under present law, the renewable energy production Tax Credit provides an income tax credit of 2.2 cents/kilowatt-hour for the production of electricity from utility-scale wind turbines under energy policy act of 992 - expires December 31, 2012" Source: AWEA Similarly, through the American Recovery and Reinvestment Act of 2009, wind project developers receive a 30% investment tax credit. See above for Clean Energy Act of 2012, which applies both to solar and to wind power.
Current Events
Clean Wind Energy Tower Announced on May 10, 2012 that the City Council of San Luis, Arizona had voted in favor of allowing CWET to build a "innovative green renewable energy Downdraft Tower Facility".
San Diego Gas & Electric Reached an agreement on May 10, 2012 with Mesa Wind Power. Included in the agreement was a 29.9 mega-watt wind farm located five miles from Palm Springs. The contract will last two years. Natural News Solar Plant The U.S agreed to build a solar power plant in California, and they spent 1.4 billion dollars doing it. It can power up to 600,000 homes in an area, while saving money.
The Cape Wind Project in Nantucket Sound has been met with a explosive outcry of residents protesting the noise, avian deaths, and aesthetics. Despite this, the project is going forward.
Statistics
Yearly emissions eliminated by generating energy from a 1 MW wind turbine instead of 1 MW of conventional sources
Over 1,500 tons of carbon dioxide, 6.5 tons of sulfur dioxide, 3.2 tons of nitrogen oxides, and 60 pounds of mercury.
Installed cost of wind energy
2-6 cents/kWh
Potential U.S. wind energy production by 2020
Enough power for 25 million homes yearly.
Wind energy produced in the U.S
16,000,000,000 kWh per year (enough power for 1.6 million homes)
Wind energy produced worldwide
65,000,000,000 kWh per year (enough power for 6 million U.S. homes)
Over 20,000 mw* of wind turbines were installed in 2007 bringing world- wide capacity to 94,112 mw, up 27% from 2006. Cheap, Low efficient wind turbines are available in the market for home use. Five nations – Germany (22,300 mw), the US (16,800 mw), Spain (15,100 mw) India (8000 mw) and China (6,100 mw) account for 80% of the world's installed wind energy capacity. Wind energy continues to be the fastest growing renewable energy source with worldwide wind power installed capacity reaching 94,112 MW in the year 2007. In terms of economic value, the global wind market in 2007 was worth about $36 billion, according to Global Wind Energy Council (GWEC). In capacity addition, the US was in the lead in 2007, followed by China and Spain. Source mw-megawatts
Stakeholders
Aviary life will be compromised if wind turbines are put up, as they could get stuck in the turbines. However, the general public will be benefited, as will the environment, because of the new green energy. Again, those working in coal and businesses producing nonrenewable energy will be harmed, but new jobs for building wind turbines and repairing wind turbines will be created.
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Talia, Paloma, Corey, Aaron
Table of Contents
Solar Power
Solar power is the harnessing of the sun's energy through eitheractive or passive means. Active Solar consists mainly of the usage of photovoltaic cells; when sunlight hits the cells, it knocks the electrons free from the atoms, and the freed electrons then move through the cell, generating electricity along the way. Another active method to capture the sun's energy is the solar thermal power plant. In the power plant, there are two methods to capture the sun's heat: the first uses u-shaped mirrors to focus the rays on a oil pipe, which then heats water to drive a steam turbine. The second works similarly, except with moveable mirrors that focus the sun on a collector tower, in which there is a reciever. Molten salt runs through the reciever and runs a generator.
Passive solar uses solar power indirectly to heat, for example, a house. Among the strategies used is one that encloses
water pipes in a black box on the roof. The black metal absorbs heat and warms the water, which the residents then use for showers, laundry, etc. Another method uses windows on the sunniest side of the building to warm heat-absorbant materials inside the house. This is called direct gain. These materials are designed to release energy during the night to heat the house. Source: National Geographic
Pros
Cons
- Manufactoring emits pollutants, greenhouse gases worse than CO2.
- Has to be a long-term investment - expensive at first.
- Solar power can not be used at night, and a system could cost between 15,000 and 30,000 dollars. To save that kind of money, it could take from three to ten years, depending on the cost of the panels and the amount of energy you need.
- Weather & pollution can affect the power output.
- Shady and tree covered areas also do not have great power output.
- Not much competition, so prices are driven up.
- You need a relatively large area to install solar panels if you want a good level of efficiency. (Source)
- Depending where you live (Arizona vs. Alaska, around many shady trees or in the desert, etc.), you will get different results with solar energy systems.(Source)
Source: Energy InformativeFederal Policy
The Renewable Portfolio Standard Requires the states to obtain a certain amount of clean energy. For example, Arizona must get 15% of their energy from renewable sources by 2025. Jeff Bingaman (D-New Mexico) speaking for the Senate Energy and Natural Resources Committee, has also proposed a bill for extending the tax credit and the Clean Energy Standard Act of 2012, requiring large utilities to obtain a certain percentage of their energy from clean sources. The percent grows with time.Potential
Solar Energy has enormous potential not only for the United States, but around the world. Even though enough sunlight falls on Earth's surface every hour to meet the world's energy demand for a year, only approximately 10,000 homes in the United States are powered entirely by solar energy - approximately 9% of the whole. It would only take around 0.3% of the world's surface to meet our electric needs via solar power - that is about the amount of roof space in Australia.The silicon (used in photovoltaic cells) from just one ton of sand can produce as much electricity as burning 500,000 tons of coal. Solar energy is also an extremely diverse source; you can use it electrically, thermally, or for basic functions such as cooking. The largest Concentrated solar power (CSP) solar power plant is in the world located in the Mojave Desert of California, and the largest photovoltaic (PV) solar power plant in the world is located in Golmud Solar Park in China (Alliant Kids Energy).
Solar Power also is a much more viable option than, for example, nuclear power. Weight for weight, advanced silicon based solar cells generate the same amount of electricity over their lifetime as nuclear fuel rods, without the hazardous waste. All the components in a solar panel can be recycled, whereas nuclear waste remains a threat for thousands of years. Also, both solar and wind power systems have 100 times better lifetime energy yield than either nuclear or fossil energy system per ton of mined materials (Energy Matters). A future for soolar power also exists in transportation; NASA powers many of its spacecraft with solar energy. In addition, an aircraft power solely by the sun crossed the USA in 1990 (Source).
Source: Green Living
Current Events
Statistics
Stakeholders
The general population will benefit from switching to solar energy. Although it is a long term investment, switching to solar energy will pay off after several years. However, those working in coal and mining industries will suffer, because of lack of jobs, if the globe goes solar. That said, they could find new jobs working in solar businesses, doing repair work, or creating solar panels.
Wind Power
Wind power is the usage of wind to generate energy through wind turbines. Wind is a free, renewable resource, with great abundance everywhere on the planet. This energy is ideal for remote locations, though it can be used anywhere. Since it can be used anywhere, if the whole world converted to using wind energy, countries would not be in debt because of reliance on other countries for oil and fossil fuels. However, the wind turbines must be a long investment, due to the great expense of each turbine - although, with the amount of money saved through the wind turbine, the wind turbine will soon pay for itself. They also generate a lot of noise, contributing to noise pollution, and can kill birds and bats. An average wind speed of 14 miles per hour is needed to convert wind energy into electricity.Wind farms currently produce enough electricity to meet the needs of more than 600,000 families in the United States.
Wind power farms generate between 17 and 39 times as much power as they consume, as compared to 16 times for nuclear plants and 11 times for coal plants, according to a study of Midwestern wind farms by the University of Wisconsin.
The average blade length is 80 feet. The height of the tower must be four times the length of the blade.
Wind is caused by uneven atmospheric heating, the rotation of the earth, and the Earth's surface irregularities. Patterns of wind flow are altered by vegetation, bodies of water, and the earth's terrain. Wind turbines modify the kinetic energy found in wind, and turn it into mechanical power. The wind turns the blades, which spin a shaft, which are hooked up to a generator that makes electricity. This energy is sent to a utility grid which sends it to consumers of energy through transmission and distribution lines. Source
Pros
(From Green Living, seia.org, and Buzzle.com)Cons
Federal Policy
The United States Congress has passed and extended several pieces of legislation to promote the use of renewable energy. "Under present law, the renewable energy production Tax Credit provides an income tax credit of 2.2 cents/kilowatt-hour for the production of electricity from utility-scale wind turbines under energy policy act of 992 - expires December 31, 2012" Source: AWEA Similarly, through the American Recovery and Reinvestment Act of 2009, wind project developers receive a 30% investment tax credit. See above for Clean Energy Act of 2012, which applies both to solar and to wind power.Current Events
Natural News Solar Plant The U.S agreed to build a solar power plant in California, and they spent 1.4 billion dollars doing it. It can power up to 600,000 homes in an area, while saving money.
Statistics
Potential
Over 20,000 mw* of wind turbines were installed in 2007 bringing world- wide capacity to 94,112 mw, up 27% from 2006. Cheap, Low efficient wind turbines are available in the market for home use. Five nations – Germany (22,300 mw), the US (16,800 mw), Spain (15,100 mw) India (8000 mw) and China (6,100 mw) account for 80% of the world's installed wind energy capacity. Wind energy continues to be the fastest growing renewable energy source with worldwide wind power installed capacity reaching 94,112 MW in the year 2007. In terms of economic value, the global wind market in 2007 was worth about $36 billion, according to Global Wind Energy Council (GWEC). In capacity addition, the US was in the lead in 2007, followed by China and Spain. Source mw-megawattsStakeholders
Aviary life will be compromised if wind turbines are put up, as they could get stuck in the turbines. However, the general public will be benefited, as will the environment, because of the new green energy. Again, those working in coal and businesses producing nonrenewable energy will be harmed, but new jobs for building wind turbines and repairing wind turbines will be created..